[OpenIndiana-discuss] Are there any issues re ZFS on 2TB disks (from WD??) with large blocksizes?

[Piotr Jasiukajtis]

On Feb 9, 2011, at 12:06 PM, Matt Connolly wrote:

> Here's my experience:
> 
> On 07/02/2011, at 11:31 PM, Piotr Jasiukajtis wrote:
>> On Feb 7, 2011, at 1:13 PM, Robin Axelsson wrote:
>> 
>>> Could someone enlighten me as to what is wrong with WD's disks, and particularly what's wrong with their EARS disks?
>> 
>> 1. They emulate 512b with a big write performance hit. 
>> Workaround is to use patched zpool or use zfs sync=disabled, however you will not use patched zpool on a boot zpool.
> 
> I have a simple setup with 2x SATA drives: 1 x Samsung Silencer HD154UI and 1 x Western Digital Green WD15EARS.
> 
> The write performance of the WD is so bad that the entire system becomes totally unresponsive, sometimes for minutes at a time, while the drive catches up with a massive backlog of writes. (Read performance is fine.) Symptoms are exactly the same as the first post in this thread:
> 
> http://community.wdc.com/t5/Desktop/Poor-performace-in-OpenSolaris-with-4K-sector-drive-WD10EARS-in/td-p/20947
> 
> I stil get these symptoms with OI-148.
Try zfs sync=disable - that works on oi_148.

>> 2. They spin down heads every 8 seconds.
> This particular problem can be overcome by using the WD3IDLE command to defeat this behaviour.
Actually it's not possible anymore with 2TB drives with the latest firmware revision.

>> 3. I have seen a few bad sector reports and bad heads on those drives.
> 
> I haven't seen any read/write errors in `zpool status` ever. (nearly one year old).
My first EARS drive comes with broken heads, second one is good so far. 
However my colleges also has some issues with those drives, after a few months of uptime they just broke (bad sectors and/or heads).

> I'm not going to get another WD * EARS drive.
Same here. I have never seen so bad drive design.


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Piotr Jasiukajtis | estibi | SCA OS0072
http://estseg.blogspot.com